Yusuke Kozaki announced that he is the designer behind the Cetoddle and Varoom lines in Pokemon Scarlet and Violet. He has also included fan art of the Pokemon. You can also see Toxel, Toxtricity, and Falinks in the picture. These three Pokemon, which debuted in Pokemon Sword and Shield, were also designed by Kozaki. [Thanks, Inside!]
For reference, Kozaki is a manga artist and character designer who has worked on many video game series. He designed characters for the No More Heroes series, Fire Emblem Awakening, Fire Emblem Fates, and AI: The Somnium Files. For Pokemon Scarlet and Violet, he contributed the designs for Varoom, Revavroom, Cetoddle, and Cetitan.
In his tweet, Kozaki said:
“Under the supervision of the developer Game Freak, I was in charge of the designs of Varoom & Revavroom and Cetoddle & Cetitan for Pokemon Scarlet and Violet. I aimed for designs that would make everyone in the world smile and get excited. I hope that they can have a good Paldean journey with everyone!”
— コザキユースケ/Yusuke Kozaki (@kymg) January 10, 2023
You can find Cetoddles and Cetitans in the Glaseado Mountain region in Paldea. If you have a Cetoddle, you can use an Ice Stone to evolve it into Cetitan. As for Varoom, you can find it in Areas One, Two, and Three. Revavrooms are also in Areas One and Three. Of course, if you have a Varoom, you can evolve it into a Revavroom as well. It will evolve at Level 40.
Pokemon Scarlet and Violet is readily available on the Nintendo Switch.